JPH01308632A - Conforming method of form plate of screen printing machine - Google Patents

Abstract

PURPOSE:To utilize a form-plate conforming function effectively, and to improve overall printing-position accuracy by moving an anchor block for an article to be printed so as to maintain positional relationship having high accuracy to an alignment desired value in the specific pattern of the article to be printed. CONSTITUTION:The man value of a plurality of the results of measurement is obtained by an arithmetic processing unit 13, and the result is transferred to a picture processor 10, and stored as an alignment desired value. An article to be printed 6 is positioned at a block 5 for the article to be printed 6 while using locating pins 7 as references, and sucked under a vacuum and fixed, a specific pattern is picture-input by video cameras 8, 9, a picture data is transferred to the picture processor 10, and a specific pattern position is picture-measured from the specific pattern picture. The result of the measurement is compared with the alignment desired value, the quantity of displacement with specified positional relationship is arithmetically operated, and data are transferred to the stage controller 13. Each motor 15, 16, 17 for adjustment is driven on the basis of the data, and the operation is repeated until the quantity of displacement of the alignment desired value and positional relationship reaches an allowance value or less. Accordingly, a printing plate 1 and the article to be printed 6 are form plate-conformed automatically, and printing is conducted in positional relationship having high accuracy when the anchor block 5 for the article to be printed is moved to a point A and printing is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for aligning a plate of a screen printing machine and a substrate to be printed. After the printing plate having the pattern is fixed to the plate fixing part of the printing press, relative positioning between the printing plate and the substrate, that is, plate alignment is performed. In this method of aligning the printing plate and the printing material, the amount of rubbing is adjusted by moving the printing material or the printing plate. The present invention is directed to the former method of moving the printing substrate and aligning the plates. As a method of moving the printing material and aligning the plates, for example, Japanese Patent Application Laid-Open No. 60-259446,
Japanese Unexamined Patent Publication No. 108555/1983 is known.

However, since this method uses the reference point on the printing plate as the alignment target value, there remains the problem that the printing plate expands and contracts during printing, causing the actual printing position to shift. As a method to solve this problem, for example, JP-A-61-12
No. 0748 proposes a method in which printing is performed on a printing material and the specific print pattern position is used as an alignment target value.

[If the invention tries to solve it! Problem 1] In the above conventional technology, no consideration is given to improving the accuracy of the alignment target value, and the result is not sufficiently satisfactory in terms of the deviation in the positional relationship between the printed pattern and the printed pattern, that is, the overall printing position accuracy. It was hard to beg. This is because the specific printing pattern position used as the matching target value is by no means stable, and depends on the configuration of the printing plate material.
It is known that the printing position varies within a range of approximately 00 μm. Therefore, even if the plate alignment accuracy is ±10 μm,
If the print position is set at a print position with a low probability when the matching target value is set, most of the final print positions will be deviated from the target position.

An object of the present invention is to effectively utilize the plate alignment function and improve overall printing position accuracy by providing a method for increasing the precision of matching target values with printing plates.

[Means to solve the problem]

In order to achieve the above object, the present invention not only has a function of measuring the position of a specific print pattern after printing on a printing material, but also statistically processes a plurality of measurement results to calculate the most probabilistic result. Estimating the high printing pattern position, for example, finding the average value and setting that position as a matching target value, and fixing the printing material so that the specific pattern on the printing material has a predetermined positional relationship with respect to that target value. It is characterized by moving the table.

[Effect]

It is possible to minimize the effects of printing dimensional errors inherent in printing, such as expansion and contraction of printing plates, and to effectively utilize highly accurate plate alignment operations, thereby improving printing accuracy for specific patterns on the printing material.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

As shown in FIGS. 1A and 1B, a printing plate 1 is fixed to a plate fixing part 2 of a screen printing machine. A guide rail 3 is disposed horizontally below the plate fixing part 2, and a conveyor table 4 is slidably provided on the guide rail 3. Therefore, the conveyance table 4 can be reciprocated between a point A below the printing plate 1 fixed to the plate fixing part 2 and a point B away from the printing plate 1. A printing material fixing table 5 is mounted on the conveyance table 4-1 so as to be movable up and down, and a positioning pin 7 for positioning the printing material 6 is embedded in the printing material fixing table 5. Although not shown, the printing material 6 is vacuum-adsorbed onto the printing material fixing table 5. A video camera 8.9 is disposed above the substrate fixing table 5 at point B to detect the left and right edges of the substrate 6, and the video cameras 8 and 9 are connected to an image processing device 10 for image processing. The device 10 includes monitor televisions 11 and 12, and an arithmetic processing device 1.
3. It is further connected to a stage control device 14. As shown in FIG. 2, the substrate fixing table 5 is provided with an X-direction adjustment motor 15, a Y-direction adjustment motor 16, and a θ-direction adjustment motor 17. It can be moved in the θ direction.

Next, the plate matching method will be explained. A printing plate 1 is fixed to a plate fixing part 2. With the printing material fixing table 5 positioned at point B, the printing material 6 is positioned on the printing material fixing table 5 with reference to the positioning pin 7, and fixed by vacuum suction. The printing material fixing table 5 is moved to point A and then raised to lift the printing material 6 to a printable position. Then, print. Next, the substrate fixing table 5 is lowered and moved to point B. Then, the specific print pattern printed on the left and right ends of the printing material 6 is input as an image using the video cameras 8 and 9, the image data is transferred to the image processing device 10, and the image of the specific print pattern is used to determine, for example, the centroid. , and image-measure the specific print pattern position. The measurement results are transferred to and stored in the arithmetic processing unit 13. This series of operations is performed multiple times, and the arithmetic processing device 13 calculates, for example, an average value of the multiple measurement results, and transfers the result to the image processing device 10. Image processing device 10
stores this value as the alignment target value.

Next, the printing material 6 is positioned on the printing material table 5 using the positioning pin 7 as a reference, and fixed by vacuum suction. Then, the video cameras 8 and 9 input images of specific patterns arranged at the left and right ends of the printing material, and the image data is transferred to the image processing device 10.
For example, concentricity is determined from the specific pattern image and the specific pattern position is image-measured. This measurement result is compared with the previous alignment target value, the amount of deviation from the predetermined positional relationship is calculated, and the data is transferred to the stage control device 13.

The stage control device 13 drives each drug dispensing motor 15, 16, 17 based on the data Jk. After driving, the specific pattern position is image-measured again, and this operation is repeated until the amount of deviation between the matching target value and the positional relationship becomes less than or equal to the allowable value. Thereby, plate matching between the printing plate 1 and the printing material 6 is automatically performed. Thereafter, by moving the printing material fixing table 5 to point A and printing, printing can be performed with a highly accurate positional relationship. Furthermore, after each printing, the specific print pattern position after printing is measured at point B, transferred to the calculation device 13, and combined with the previous measurement results to obtain an average value and set it as a new matching target value, thereby further improving printing accuracy. We can expect improvement.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, in a screen printing machine having a plate matching function, the accuracy of the matching target value is improved, and by performing plate matching with respect to the target value, a high-precision plate The alignment function is effectively utilized, improving overall printing accuracy.

[Brief explanation of the drawing]

1A and 1B show an embodiment of the present invention;
Figure A is a plan view, and Figure 1B is a front view. FIG. 2 is a plan view of the substrate fixing table.

Claims (1)

[Claims] 1. Print on the substrate, measure the specific print pattern position multiple times, set the average value of the multiple specific pattern position measurement results as the matching target value with the printing plate, and measure the specific pattern on the substrate. A plate alignment method for a screen printing machine characterized by moving a substrate fixing table so as to maintain a highly accurate positional relationship with respect to an alignment target value.